It is not possible to give a sensible answer to this question. The highest common factor (HCF) refers to a factor that is COMMON to two or more numbers. You have only one number in the question!
The HCF is 1.
The GCF is 1.
The GCF is 15.
HCF(26, 45) = 1. The numbers are co-prime.
The GCF is 5.
3
5
15
9
It is: 5
It is: 5
The hcf of 12 & 36 is 12